GUI_sifravimas.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;

namespace WpfApplication1_sifravimas
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }

        string sifruok(string txt, int k = 1)
        // https://en.wikipedia.org/wiki/Caesar_cipher
        // k - per kiek vietu pastumti simboli ASCII lenteleje
        // http://www.asciitable.com/index/asciifull.gif
        {
            string rez = "";
            foreach (char simb in txt) // su kiekvienu simboliu is teksto
            {
                int nr = (int)simb;    // paverciame simboli i skaiciuka (jo numeri ASCII lentelej)

                // Kodavimo "burtai"
                // rez += (char)(nr + k); // pastumiam numeri, paverciam atgal i simboli, ir pridedam prie rezultato
                int naujas_nr = nr + k;     //  pastumiam numeri
                char naujas_simbolis = (char)naujas_nr; // paverciam atgal i simboli
                rez += naujas_simbolis;     //  ir pridedam prie rezultato

                Console.WriteLine(simb + " --> " + (char)(nr + k));
            }
            return rez;

        }


        private void button_Click(object sender, RoutedEventArgs e)
        {
            textBox.Text = sifruok(textBox.Text); // uzsifruojam

        }

        private void button1_Click(object sender, RoutedEventArgs e)
        {
            textBox.Text = sifruok(textBox.Text, -1); // atsifruojam
        }
    }
}